I'd say in any case seize the weapons and destroy the dealer if needed.
If another character is helping him, apprehend him as well.
Doesn't matter if Igiss is flying the char, if it's what needs to be done in-RP, you do it.
Had he say.. tried to solve the problem in-RP and offer you a bribe, you could take it if you want to RP that way. If you don't, noone can force you to.
You can RP him bribing you if you wish, but he cannot force you to RP how he wants. I'd call it a violation of server rules even the one about damaging server gameplay, not just faction rules. But in any case, I'm certain for the faction rules bit, not for the rules bit, as that particular rule is subject to interpretation and were this a sanction report I guess the admins'd discuss it extensively.
As for your senior officer flying that ship and abusing his position in OOC, I'd tell you to contact Zapp immediately and he will solve the problem.
Contact your faction leader. I know what I would have done in his place.
<span style="font-familyalatino Linotype">
<span style="color:#000000">All morons hate it when you call them a moron.
alatino Linotype">